1. Field of the Invention
The present invention relates generally to the field of wireless communications, and in particular, to a system and method for extending the range of a base unit.
2. Background Art
Presently, home wireless networks include a base unit (e.g., remote control unit) and one or more devices remote from the base unit. Upon a command from the remote control unit, the device to be controlled responds accordingly. For example, a remote control for remotely controlling lamps and other lighting devices in a home can selectively connect or disconnect the lighting device from a power source. Another example is a remote control unit for selectively activating an entertainment center, such as a stereo system or a television. The base unit can be as simple as a remote control unit that employs infra-red (IR) signals or can be as sophisticated as a personal computer (PC) that employs a communication card to transmit radio-frequency (RF) signals. An automatic garage opener system is another example of a wireless system that employs RF signals for communication.
However, present home wireless systems can suffer from the following disadvantages. First, the effective range of remote control units is limited. For example, for devices having an IR interface, once the remote control unit is removed from the line-of-sight of the device, the device is effectively xe2x80x9cout-of-rangexe2x80x9d and can no longer be controlled by the remote control unit. Even with devices that employ an RF interface (e.g., automatic garage door openers), the remote control unit must be xe2x80x9cin rangexe2x80x9d before it can activate the device. Consider a large three story home, where the owner is on the third floor in a room that is in a far corner of the home, and the owner remembers that the garage door is open. Even if the owner attempted to employ the remote garage door opener (i.e., the remote control unit) to close the garage door, the barriers in the home (i.e., walls), layout of the home, and the distance between the remote garage door opener and the main unit in the garage may preclude the remote garage door opener from communicating with the main unit.
Second, interference can degrade or distort an intended command or instruction. If the placement of the devices relative to the base unit is not ideal, an inappropriate distribution of the transmitted signal occurs, resulting in loss of the signal, degradation of the signal, or an erroneous signal. Depending on the topology of the home (e.g., the location and thickness of the walls) and the number of barriers or objects in the home, a transmitted signal can be adversely affected by interference. Interference can stem from a source that is external to the wireless system (e.g., another system generating separate RF signals) or from reflected signals that are generated internal to the wireless system. The transmitted signal can also be attenuated by barriers or objects that completely block or partially occlude the signal path. Shielding effects can also attenuate the transmitted signal.
Accordingly, there remains a need for an improved system and method for remotely controlling one or more devices that extends the range of a base unit, that improves signal distribution, that flexibly adapts to and facilitates the convenient set-up and re-configuration of the wireless system, and that is compact and cost effective.
It is therefore an object of the present invention to provide a system and method for a base unit to extend its effective range of communication with devices to be controlled.
It is another object of the present invention to provide a system that improves signal distribution by employing network modules adapted to couple to any conventional powered outlet.
It is yet another object of the present invention to provide a network module that receives power from a conventional powered outlet socket and that does not require a separate power source.
It is yet another object of the present invention to provide a network module to house the repeater and network decoder electronics.
It is yet another object of the present invention to provide a network module that can receive a light bulb and control the on/off state of the light bulb.
It is yet another object of the present invention to provide a network module that can function as an electrical outlet and control the on/off state of the outlet.
In order to accomplish the objects of the present invention, there is provided a system and method for extending the range of a base unit so that devices that were previously out-of-range can be controlled by employing the present invention. The system includes a base unit, at least one network extender, and a plurality of devices to be controlled.
In accordance with one embodiment of the present invention, the network extender includes a repeater for receiving a control signal on a first frequency, or using a first code, from the base unit and re-transmitting the control signal on a second frequency or a second code. The network extender also includes a network decoder for receiving the control signal on the second frequency or code from the repeater, decoding the control signal, and providing the control signal to an intended device via a direct link, an RF link, or an IR link.
In accordance with another embodiment of the present invention, the network extender includes a first repeater, a second repeater, a first network decoder, a second network decoder, a first plurality of devices, and a second plurality of devices. The first repeater and the second network decoder are housed in separate network modules. The second repeater and the first network decoder are integrated into a single network module. The first repeater receives a control signal on a first frequency, or using a first code, from the base unit and re-transmits the control signal on a second frequency or second code. The second repeater receives a control signal on the second frequency or code from the first repeater, and depending on the nature of the control signal, either re-transmits the control signal on a third frequency or code, or its integrated network decoder provides the control signal to one of the first plurality of devices via a direct link, an RF link, or an IR link. The second network decoder receives the control signal on the third frequency or code from the second repeater, decodes the control signal, determines if the command or instruction is intended for one of the second plurality of devices controlled by the second network decoder, and if so, provides the control signal to the intended device via a direct link, an RF link, or an IR link.
The repeaters, network decoders, and integrated repeater and network decoder units of the present invention are each housed in a separate network module that is adapted to couple to a powered outlet and to receive a powered device. The powered outlet can be a light bulb socket or an electrical outlet, and the powered device can be any device that requires electrical energy for its operation. Each network module receives power from the powered outlet and provides this power to the repeater and/or network decoder. Each network module further includes electronics to control the on/off state of the powered device.
In accordance with one aspect of the present invention, the first, second and third frequencies can be the same frequency, or can be different frequencies. Similarly, the first, second and third codes can be the same or different codes.